This invention relates to a stirring mill for fine grinding and/or dispersal of flowable grinding stock. The present invention relates more particularly to such a stirring mill which includes a grinding container with a rotatably drivable shaft equipped with stirring members. The grinding container is provided with a grinding-stock inlet in the vicinity of one end and a ground-stock outlet in the vicinity of the other end. A separating device is disposed in front of the ground-stock outlet to retain grinding media located in the grinding container, the separating device being formed by annular disks disposed concentrically on a shaft, the disks being rotatable relative to one another and forming radial spaces between them. The width of the spaces is less than the diameter of the smallest unit of grinding media.
A stirring mill of the above-mentioned type is known from U.S. Pat. No. 3,311,310 wherein a radial space is formed by an annular disk fitting around a mixer shaft and an opposing ring mounted immovably on a grinding container, the width of the space being adjustable. This mixing device in which a grinding effect is also produced simultaneously in the spaces, has proven to be extraordinarily satisfactory; however, problems arise when adjusting the space width.
German Offenlegungsschrift (Laid Open Patent Application) No. 1,507,493 likewise discloses a stirring mill of the type described hereinabove, in which an annular disk is disposed between two opposing rings mounted immovably in the grinding container, the annular disk being connected nonrotatably with the mixing shaft and being adjustable axially relative to the shaft. The disk delimits spaces arranged in parallel relative to the opposing rings. Here agains problems arise in adjusting the opposing rings.
German Auslegeschrift (Published Patent Application) No. 2,112,605 discloses a stirring mill in which a radial space is formed between an opposing ring mounted immovably opposite a grinding container and an annular disk. The annular disk is mounted immovably relative to a shaft separate from the mixing shaft, the annular disk being provided with driving means in the form of propeller blades, so that it can rotate freely with flow of grinding stock.
German Auslegeschrift (Published Patent Application) No. 2,446,341 discloses a stirring mill in which a packet of annular disks arranged concentrically relative to one another is provided as a separating device to hold back the grinding media. The disks delimit radially extending spaces; an annular disk is always mounted immovably and alternately in the grinding container, while the other annular disks can be set oscillating by a vibrating drive.
German Offenlegungsschrift (Laid Open Patent Application) No. 1,757,953 discloses a stirring mill in which a rotating screen in the form of a hollow body is provided as the separator. The purpose of the rotational movement of the screen is to prevent clogging of the screen by the grinding media.